Combined electric-connection plug and socket and switch.



W. W. BUCKTON.

COMBINED ELECTRIC CONNECTION PLUG AND SOCKET AND SWITCH.

APPLICATION FILED JUNE 1., 1908.

Patented Dec. 20, 1910.

2 8KBBT8SHEET 1.

W. W. BUCKTON.

COMBINED ELECTRIC CONNECTION PLUG AND SOCKET AND SWITCH.

APPLICATION FILED JUNE 1, 1908.

978,841 Patented Dec. 20, 1910.

2 SHEETS-SHEET 2.

WILLIAM w. BUCK'ION,

OF LONDON, ENGLAND.

COMBINED ELECTRIC-CONNECTION PLUG AND SOCKET AND SWITCH.

Specification of Letters Patent.

Patented Dec. 20, 1910.

Application filed June 1, 1908. Serial No. 436,074.

To all whom it may concern:

Be it known that I, lVILLiAM 'oonrnn llncu'rox, a subject of the King of Great Britain, and resident of 72-Victoria street, \Vestminster, London, S. lV., England, consulting engineer, have invented a new and useful Improved Combined Electric-Connection Plug and Socket and Switch, of which the following is a. specification.

The present invention relates to a combined electric connection plug and socket, and switch, and in particular to that kind of socket which, on the plug being inserted in it, is capable of rotation through a portion of a revolution to operate the switch to open or close the circuit.

- \Vhile plugs and sockets combined with a switch for interrupting the circuit before the plug is witlulrawn from the socket are already known, they have hitherto for. the most part been open to the objection that there is nothing to prevent the plug from being withdrawn from the socket without the current being first switched off, or to prevent similarly the plug being inserted with the switch in the on *position, so that the object of the combination is not attained.

i kccoriling to my invention I eonstructa plug and socket so that the plug cannot be withdrawn until the current through the connection has been switched off; neither can the plug be inserted in the socket unless the switch is in the off position. In other words, the terminal pins of the plug cannot be improperly used, as a switch, to either break or complete the circuit simply by removing or inserting the plug from or into the socket. These operations can only be done when the terminals of the socket have been rendered dead due to its being necessary for the switch to be in the ott position before the plug can either be with drawn or inserted.

I am aware that other devices have already been invented to bring about a locking of the plug to the switch and socket cover on the socket being turned to switch on the current, but they have not so far as I am aware been found satisfactory in practice, as they rendered the construction of the plug and socket somewhat complicated.

My invention is illustrated in the accompanying drawings.

Figure-lisa plan view of a socket and switch and socket cover to which my invention has been applied. Figs. 2 are elevation and under plan 'views respectively of the corrcspomling plug. Fig. 3 is a plan view of acombiued plug and socket and switch with the-cover shown in Fig. 1 removed. Figs. 4; are views corresponding to Figs. 2 of a modified form of plug of known construction to which my invention has been applied. Fig. 5 is a plan view of a socket and. switch and socket cover to which my invention has been applied in a slightly different manner. Figs. 6 are elevations at right angles to each other of the plug for use with the socket shown in Fig. 5. Fig. 7 shows elevations partly in section of the socket and switch shown in Fig. 1, the revoluble portion being shown detached from its base and one contact only being shown, viz., that which engages the left hand con 'tflct blade on the revoluble portion.

Referring now to Figs. 1 to 3 within the cover a is arranged a switch and socket of well known construction, 9 g being the contact sleeves in the revoluble portion m which is made to turn about the pivot n, carried by the plate 0. This plate 0 is secured to the base a by screws 7) This revoluble portion is furnishedwith two arms or blades a: on, each in electrical connection with one of the sleeves g g. Secured to the base are the spring plates y 1 between which the blades a: m are adapted to fit closely, on the part m being turned on its pivot to switch on the current. Terminal screws 10 w are secured to the base 2, in electrical.

contact with the spring lates y y. A-spring 8 tends to ull the revo uble part m around into the o position, except when the blades :1: a: are turned fully into the on position. The cover a may be of metal or any-other suitable material and is made to screw on to the base a or is otherwise fixed thereto and is provided with bayonet-shaped stepped recesses c c d d. On the plug e, which is furnished with the usual split pins f f for provide projections h 71 arranged substantially parallel with the pins vide them at their upper en s with recesses engaging in the sleeves g g in the socket, I

f,. and I prok i, which when the plug has been inserted a to its full extent in the socket will be opposite the recessed edges of the cover a andwill allow the socket to be turned to put the switch into the on position; this cannot be done unless the lug ispushed right home inthe socket, as t e pro ections 12. z fill the the side of the insulatin of the pa wider parts a (Z of the recesses in the cover a and prevent the plug and socket being turned until the grooves h '4" in the projections h i are opposite the narower recesses 0 d. This insures that the circuit cannot be completed until proper and full contact has been made through the connection. The plug 0 is now. locked to the cover a and the pins f 1 cannot be withdrawn from the sleeves g g in the socket unless the socket is first turned back so that the switch is in the off position and the arms as :0 brought out of contact with the plates y 3 In other words thecurrent cannot be interrupted by withdrawing the plug from the socket when the switch is in the on position; nor can the plug be inserted in thesocket unless the switchis in the ofl position. I

The projections h i may be an integral part of the usual insulating disk or plate 7' to which the split pins f f of the plug 6 are attached, or they may be separate. In the latter case the projections may .take the form of a single bent bar fitting into a recess in the insulating disk formed preferably in disk adjacent to the plug e, a layer (not s own in the drawing) of mica or the like being inserted 172- tween the plug 6 and the disk j. The projections may however be made separate and insulated from one another by a fillet of insuliting material as shown in Figs. 2 and 4 at In order that the plug may be properly inserted in the socket so as to control the correct lead where this is essential, I may -make the projections h i on the plug 6 of different sizes as shown in Figs. 2, and the recesses 0 cl in the cover a of corresponding sizes, so that, for instance, the projection i fits into the recess d,'bujt not into the recess 0. The plug 6 can then only be inserted in one position.

Though I have shown the projections h z" of different sizes in the drawings I wish it to be understood that this feature is not essential to the operative carrying out of my invention.

In Fi s. 4 is illustrated a modified form shown in Figs. 2. Here I insure't-hat t e plug is inserted in its socket in the right way by furnishing the plug 6 with one pin f'and one sleeve 9 in wellknown manner, and providing 3. corresponding sleeve and pin on the socket. The projections h i cart then be made of the same size, and this simplifies manufacture.

In Figs. 5 and 6 is illustrated an alternative methodof putting my invention into practice. The recesses a d in the socket cover are not stepped in this case, but recesses are made in the socket, which :when the socket is in the off position are opposite the recesses in the socket cover, and

allow the projections h i to be inserted. ()n the socket being turned into the on position, the projections h i will lock under the edge of the cover a as before.

I do not confine myself necessarily to Q-pin terminal plugs as the invention is equally applicable to plugs with other forms of terminal projections though the invention herein described and the drawings shown refer to this type as being convenient.

What I claim as my invention and desire to secure by Letters Patent is 1. In a combined socket and plug and switch, the combination of a plug, a revoluble portion on said plug having contaot' pins. sleeves on the revoluble portion into ,which the contact pins and plugs are inserted, contacts on the revoluble port-ion oft-he socket for switching on the current when this portion is partially revolved, a socket cover open abovethe revoluble portion of the socket and having recesses in its inner edge, vertical projections on the plug 'extending parallel with the contact pins thereon and so placed as to be opposite the recesses in the edge of the cover when the plug is inserted in the socket when the switch is in the ofl position and whereby the recesses in said projections engage the edges of the socket cover when the switch is turned to the on position.

2. A combined plug .and socket and switch, comprising a plug, in combination with a socket having a revoluble portion, contacts on the revoluble portion for switching on the current when this rtion is partially revolved, means for making detachable electrical contact between the plug and the revoluble portion of the socket, a socket cover, a stepped recessed portion in the edge of the cover, a vertical pro'ection on the plug so placed as to be opposite the recessed portion in the edge of the cover when the plug is inserted in the socket and the switch is in the off position said projection having a shoulder with which the edge of the socket cover en ges when the switch is turned to the on osition.

3. A- combined plu an socket and switch comprising a p ug in combination 11 with a socket having a revoluble portion, contacts on the revoluble portion for switching on the current when this portion is partially revolved, a contact pin and a contact sleeve on the plug, a corresponding 1 contact sleeve and a contact pin on the revoluble portion of the socket for engaging the corresponding parts of the plu asocket cover, a recessed portion in the e ge of the cover, a vertical projection on the plug so placed as to be opposite the recessed portion in the edge of the cover when the plug is inserted in the socket and the switch is in the ofl position, and a recess in said projecengages when the switch is turned to the on position.

4c. In a combined plug and socket and switch, the combination of a plug, a socket having a revoluble portion and provided with contacts, a socket base having contacts adapted to engage with the contacts on the "revolubleportion when the latter is partially revolved, means for making electrical contact between the plug and the revoluble portionof the socket, a socket cover having recesses in its edges, projections on the plug so placed as to be opposite the recesses in the edge of the cover when the plug is inserted in the socket and the switch is in the ofi' position and said rojections having interlocking portions w ich engage the recesses of the socket cover when the switch is turned to the on position and differently shaped in cross section for insuring that the plug can be inserted in the socket in one way only.

5. In a combination plug and socket and switch, the combination of a switch portion having two contacts with a plug portion provided with two contacts respectively en: gaging the contacts of the switch portion, and interlocking parts for holding the plug portion to the switch portion when the switch is closed and unlocking the said parts when the switch is in its open position, said contacts on the plug and the switch portion maintaining their electrical connection while the interlocking parts are thrown into either the locked or unlocked positions In testimony that I claim the foregoing as my invention I have signed my name inpresence of two witnesses this 19th day of May 1908, v

EV. W. BUCKTON,

Witnesses:

LovELL U. RIDDIE, BERNARD J. KENNEDY, 

